Storage electric water heater

ABSTRACT

A storage electric water heater includes a tank, an inlet tube, an outlet tube, an isolating member, and a heating device, wherein the tank has a storing space. The inlet tube and the outlet tube are disposed in the tank. The isolating member is disposed in the storing space to divide the storing space into a first chamber and a second chamber. The first chamber communicates with the inlet tube and the outlet tube. The heating device is disposed in the second chamber and includes a tube body and a heating element. Two ends of the tube body communicate with the first chamber, so that water in the first chamber could enter an interior of the tube body. The heating element is disposed on a tube wall of the tube body. Thermal energy generated by the heating element could be transferred to the interior of the tube body via the tube wall to heat up water in the tube body, thereby facilitating the thermal convection of water in the first chamber.

BACKGROUND OF THE INVENTION Technical Field

The present invention relates generally to an electric water heater, andmore particularly to a storage electric water heater.

Description of Related Art

A conventional storage electric water heater includes a storage tank anda heating pipe, wherein an interior of the storage tank has a storingspace for containing water. The storage tank is disposed with an inlettube and an outlet tube which communicates with the storing space. Theheating pipe is disposed in the storage tank. The heating pipe has aheating wire inside. When the heating wire is energized, thermal energycould be transferred to the water via a shell of the heating pipe toheat water.

Since the storage tank of the storage electric water heater stores hotwater, so that a user could easily access the hot water at any time,thereby enhance a convenience of life. However, the heating pipe of theconventional storage electric water heater is merely soaked in water,and water in the storing space of the storage tank stands still, so thethermal convection is not good during the heating process. Therefore, toheat water in the tank to a predetermined temperature needs more heatingtime, so that the heating efficiency of the storage electric waterheater is reduced.

BRIEF SUMMARY OF THE INVENTION

In view of the above, the primary objective of the present invention isto provide a storage electric water heater that is able to enhancethermal convection during a heating process.

The present invention provides a storage electric water heater includinga tank an inlet tube, an outlet tube, an isolating member, and a heatingdevice, wherein the tank has a storing space. The inlet tube and theoutlet tube are respectively disposed in the tank. The isolating memberis disposed in the tank and located in the storing space. The isolatingmember divides the storing space into a first chamber and a secondchamber. The first chamber communicates with the inlet tube and theoutlet tube and contains water. The heating device is disposed in thesecond chamber and includes a tube body and a heating element. The tubebody has a first end and a second end which respectively communicatewith the first chamber, so that water in the first chamber is able toflow into an interior of the tube body; the heating element is disposedon a tube wall of the tube body, wherein thermal energy generated by theheating element is transferred to the interior of the tube body via thetube wall of the tube body to heat the water in the interior of the tubebody.

By communicating the two ends of the tube body with the first chamberand heating the tube body, the thermal convection in the first chambercould be improved. Besides, since the second chamber is located in thetank, the thermal energy generated by the heating device could be fullyutilized.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The present invention will be best understood by referring to thefollowing detailed description of some illustrative embodiments inconjunction with the accompanying drawings, in which

FIG. 1 is a schematic view of the storage electric water heater of afirst embodiment according to the present invention, wherein the arrowsrepresent the direction of the water flow;

FIG. 2 is a schematic view of the heating device of the storage electricwater heater of the first embodiment according to the present invention;

FIG. 3 is a schematic view of the storage electric water heater of asecond embodiment according to the present invention, wherein the arrowsrepresent the direction of the water flow; and

FIG. 4 is a schematic view of the heating device of the storage electricwater heater of a third embodiment according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

As illustrated in FIG. 1 and FIG. 2, a storage electric water heater 1of a first embodiment according to the present invention includes a tank10, an isolating member 22, and a heating device 30.

The tank 10 has a storing space 12 inside, wherein a tank body of thetank 10 is disposed with an inlet tube 14 and an outlet tube 16. Theinlet tube 14 and the outlet tube 16 communicate with the storing space12. A shell 18 is disposed around the tank 10, and an insulated material20 is disposed between the shell 18 and the tank 10. A bottom portion ofthe shell 18 has a base 19. The inlet tube 14 and the outlet tube 16extends out of the shell 18. In the current embodiment, a location ofthe outlet tube 16 is higher than a location of the inlet tube 14.Namely, a distance between the inlet tube 14 and the base 19 is shorterthan a distance between the outlet tube 16 and the base 19.

The isolating member 22 is disposed in the tank 10 and is located in thestoring space 12 to divide the storing space 12 into a first chamber 122and a second chamber 124, wherein the first chamber 122 communicateswith the inlet tube 14 and the outlet tube 16. Water inputted throughthe inlet tube 14 is stored in the first chamber 122. A volume of thefirst chamber 122 is greater than a volume of the second chamber 124,and the first chamber 122 surrounds the second chamber 124.

The isolating member 22 has a top portion 24 and a body 26, wherein atop end of the body 26 is connected to the top portion 24; a bottom endof the body 26 is an open-end, and a periphery of the bottom end of thebody 26 is connected to a bottom portion of the tank 10. The isolatingmember 22 has a first surface 262 and a second surface 264 which faceopposite directions, wherein the first surface 262 faces toward thefirst chamber 122, and the second surface 264 faces toward the secondchamber 124. In the current embodiment, the first surface 262 and thesecond surface 264 are located on the body 26. The bottom end of thebody 26 is disposed with an enclosing member 28.

The heating device 30 is disposed in the second chamber 124 and includesa tube body 32 and a heating element 34. The tube body 32 has a firstend 322 and a second end 324 which respectively communicate with thefirst chamber 122, so that water in the first chamber 122 could flowinto an interior of the tube body 32, and water in the interior of thetube body 32 could flow into the first chamber 122. The heating element34 is disposed on a tube wall of the tube body 32, and an air space 38is disposed between the heating element 34 and the second surface 264.In other words, the heating element 34 does not directly contact withwater.

In the current embodiment, a location of the second end 324 of the tubebody 32 is higher than a location of the first end 322 of the tube body32. Namely, a distance between the second end 324 of the tube body 32and the base 19 is greater than a distance between the first end 322 ofthe tube body 32 and the base 19. The first end 322 of the tube body 32communicates with the first chamber 122 via a connecting tube 40,wherein the connecting tube 40 passes through the bottom portion of thetank 10 and the enclosing member 28. A location of an inlet end 402 ofthe connecting tube 40 is lower than the location of the inlet tube 14.The second end 324 of the tube body 32 passes through the top portion 24of the isolating member 22 and communicates with the first chamber 122.The second end 324 is located between the outlet tube 16 and the inlettube 14. Some of the water inputted through the inlet tube 14 flows intothe tube body 32 of the heating device 30 via the connecting tube 40 andthen overflows from the second end 324 of the tube body 32. Preferably,a level of water in the first chamber 122 is above the second end 324 ofthe tube body 32.

Practically, the first chamber 122 could be disposed with a minimumlevel sensor 42 and a maximum level sensor 44, wherein the minimum levelsensor 42 is located above the outlet tube 16. When the minimum levelsensor 42 detects that a level of water is lower than a firstpredetermined level, a water supplying device (not shown) is activatedto supply water through the inlet tube 14, until the maximum levelsensor 44 detects that a level of water reaches a second predeterminedlevel. When a level of water reaches a second predetermined level, themaximum level sensor 44 stops the water supplying device supplyingwater.

In the current embodiment, the tube body 32 is made by an electricallyinsulating material, such as a quartz tube or a ceramic tube. Theheating element 34 includes a nano-carbon coating 342 which is coated onthe tube wall of the tube body 32 to increase a heating area. Thenano-carbon coating 342 is disposed with two electrodes 344 which arerespectively connected to two power wires 36. The two power wires 36passes through the enclosing member 28. The tube body 32 separates thenano-carbon coating 342 from water in the tube body 32 to prevent thenano-carbon coating 342 from touching the water, thereby avoiding anelectrical leakage.

When an electric current is passed through the two power wires 36, theheating element 34 generates thermal energy, wherein the thermal energygenerated by the heating element 34 is transferred to the interior ofthe tube body 32 via the tube wall of the tube body 32 to heat the waterin the interior of the tube body 32. When water in the interior of thetube body 32 is heated, water flows upwardly, namely in a direction fromthe first end 322 to the second end 324 of the tube body 32, so that atemperature of water above the second end 324 is higher than atemperature of water below the second end 324. Since the second end 324of the tube body 32 is closer to the outlet tube 16, and the location ofthe outlet tube 16 is higher than the location of the inlet tube 14,water which is hotter above the second end 324 in the first chamber 122flows downwardly, namely in a direction from the second end 324 to thefirst end 322 of the tube body 32, due to thermal convection, therebyforming a circulation without an assistance of a convection device. Evenif additional cool water flows into the first chamber 122 through theinlet tube 14, cool water is brought into the tube body 32 and is heatedto be hot water. In other words, during a heating process, the tube body32 could facilitate the circulation due to thermal conduction in thefirst chamber 122.

The thermal energy of the heating element 34 could be transferred to thefirst chamber 122 via the isolating member 22. In the currentembodiment, the second surface 264 of the isolating member 22 couldoptionally be disposed with a thermally conductive layer 46 which facesthe heating element 34. Preferably, the thermally conductive layer 46 isa nano-carbon coating and could enhance an ability to conduct thethermal energy from the heating element 34 to the isolating member 22,so that the thermal energy of the heating element 34 could be utilizedeffectively. The enclosing member 28 could prevent thermal energy in thesecond chamber 124 from dissipating into the atmosphere through thebottom end of the body 26.

As illustrated in FIG. 3, a storage electric water heater 2 of a secondembodiment according to the present invention is configured basicallysimilar to that of the first embodiment, but in which a connecting tube48 for connecting the first end 322 of the tube body 32 and the firstchamber 122 passes through the body 26 of the isolating member 22. Withsuch design, the connecting tube 48 could also achieve a function tosupply water in the first chamber 122 to the tube body 32.

As illustrated in FIG. 4, a heating device 50 of a storage electricwater heater of a third embodiment according to the present inventionhas almost the same structure as that of each of the embodiments, exceptthat a heating element of the heating device 50 is a heating pipe 52which is coiled around a tube body 54 to increase a heating area. Afteran electric current is passed through the heating pipe 52, the thermalenergy generated by the heating pipe 52 could also be transferred to aninterior of the tube body 54 via a tube wall of the tube body 54 to heatthe water in the interior of the tube body 54. The heating pipe 52 couldbe made of a metal material.

In an embodiment, the heating pipe 52 could also include an inductioncoil to heat the tube body 54 of the metal material.

In view of the above, in the storage electric water heater of thecurrent application, the thermal convection in the first chamber duringthe heating process could be enhanced by communicating the two ends ofthe tube body with the first chamber. Additionally, since the secondchamber is located in the tank, the thermal energy generated by theheating device could be fully utilized. The heating element is separatedfrom water by the tube body, so that the could be avoided.

It must be pointed out that the embodiment described above is only apreferred embodiment of the present invention. All equivalent structureswhich employ the concepts disclosed in this specification and theappended claims should fall within the scope of the present invention.

What is claimed is:
 1. A storage electric water heater, comprising: atank having a storing space; an inlet tube and an outlet tuberespectively disposed in the tank; an isolating member disposed in thetank and located in the storing space to divide the storing space into afirst chamber and a second chamber; the first chamber communicates withthe inlet tube and the outlet tube and is adapted to store water; and aheating device disposed in the second chamber and comprises a tube bodyand a heating element; the tube body has a first end and a second endwhich respectively communicate with the first chamber, so that water inthe first chamber is able to flow into an interior of the tube body; theheating element is disposed on a tube wall of the tube body, wherein athermal energy generated by the heating element is transferred to theinterior of the tube body via the tube wall of the tube body to heat thewater in the interior of the tube body.
 2. The storage electric waterheater of claim 1, wherein the tube body is made by an electricallyinsulating material, and the heating element comprises a nano-carboncoating which is coated on the tube wall of the tube body.
 3. Thestorage electric water heater of claim 1, wherein a location of thesecond end of the tube body is higher than a location of the first endof the tube body, and the first end of the tube body is closer to theinlet tube than the second end of the tube body.
 4. The storage electricwater heater of claim 3, wherein a location of the outlet tube is higherthan a location of the inlet tube, and the location of the second end ofthe tube body is between the location of the outlet tube and thelocation of the inlet tube.
 5. The storage electric water heater ofclaim 3, wherein the first end of the tube body communicates with thefirst chamber via a connecting tube, and a location of an inlet end ofthe connecting tube is lower than a location of the inlet tube.
 6. Thestorage electric water heater of claim 5, wherein the connecting tubepasses through a bottom portion of the tank.
 7. The storage electricwater heater of claim 5, wherein the connecting tube passes through theisolating member.
 8. The storage electric water heater of claim 1,wherein the isolating member has a first surface and a second surfacewhich face opposite directions; the first surface faces toward the firstchamber, and the second surface faces toward the second chamber; an airspace is disposed between the heating element and the second surface. 9.The storage electric water heater of claim 8, wherein the thermal energyof the heating element is transferred to the first chamber via theisolating member.
 10. The storage electric water heater of claim 9,wherein the second surface of the isolating member is disposed with athermally conductive layer which faces the heating element.
 11. Thestorage electric water heater of claim 10, wherein the thermallyconductive layer is a nano-carbon coating.
 12. The storage electricwater heater of claim 1, wherein the isolating member has a top portionand a body; a top end of the body is connected to the top portion of theisolating member, so that the top portion and the body form the secondchamber; a bottom end of the body is an open-end; the bottom end of thebody is connected to a bottom portion of the tank.
 13. The storageelectric water heater of claim 12, wherein the bottom end of the body isdisposed with an enclosing member.
 14. The storage electric water heaterof claim 1, wherein the first chamber surrounds the second chamber.